JP2683266B2 - Method for manufacturing connector ferrule with filter for optical fiber - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a connector fiber for an optical fiber provided with an optical filter for removing an optical signal of an unnecessary wavelength in a line for transmitting and receiving an optical signal of a plurality of wavelengths. It relates to a rule manufacturing method.

[Prior Art] Optical fibers may be used by transmitting optical signals of a plurality of wavelengths to one fiber in an optical fiber line. For example,
The transmitter / receiver installed at one end has two wavelengths of 1.3μ.
m and 1.55 μm, the line is branched at the other end and transceivers are installed at each end, one of which has a wavelength of 1.3 μm and the other of which has a wavelength of 1.55 μm.
In a line that transmits / receives an optical signal with a wavelength of, when an optical signal with a wavelength of 1.55 μm is transmitted to a line on the side that transmits / receives only a wavelength of 1.3 μm, it is received as noise. It is necessary to block the optical signal, and similarly, it is also necessary to block the optical signal having the wavelength of 1.3 μm on the other line for transmitting and receiving only the wavelength of 1.55 μm.

Therefore, a connector ferrule 40 with a filter for optical fiber as shown in Fig. 4 (a) is inserted in the part where the optical fiber is connected to the transceiver, and the optical signal of the unnecessary wavelength is reflected there, and the required wavelength is reflected. I am trying to transmit only. That is, for example, a part of the ferrule element 41 made of ceramic in the longitudinal direction is provided with a notch 43 with a certain angle θ so as to cross the optical fiber insertion hole 42 provided in the axial direction, and the gap 43 Inject the curable resin adhesive 45 into the optical filter 44 and insert the optical filter 44 into it, or insert the adhesive 45 on both sides of the optical filter 44 into the gap of the notch 43 and heat it to make the notch 43. The surface and the optical filter 44 are bonded and solidified. In the figure, reference numeral 46 is an optical fiber inserted into the insertion hole 42.

Here, the certain angle θ is a predetermined tilt angle selected depending on the wavelength to be removed with respect to the plane perpendicular to the axis of the optical fiber insertion hole 42, and the optical filter is set at this angle θ.
By installing 44, the optical signal of the unnecessary wavelength that has propagated through the optical fiber 46 here is almost completely reflected and removed.

[Problems to be Solved by the Invention] An enlarged view of the state in which the optical filter 44 is inserted into the notch 43 and fixed by the curable resin adhesive 45 is shown in FIG. Has been done. The optical filter 44 is formed by forming an optical filter film 48 on one surface of a glass substrate 47, and the surface of the optical filter film 48 is one surface of the cut 43, that is, a plurality of wavelengths including unnecessary wavelengths are transmitted. It is necessary to bond the optical filter 44 in parallel with the surface of the optical filter 44, but since the thickness of the notch 43 is larger than the thickness of the optical filter 44, the optical filter 44 may tilt in the notch 43 as shown in the figure. If the adhesive fiber is bonded and solidified as it is, the angle formed by the surface of the optical filter 44 with respect to the surface perpendicular to the insertion hole 42 of the optical fiber 46 becomes θ ₁ . When this happens, the optical fiber 46
Since the reflection angle of the optical signal of the unnecessary wavelength that has proceeded to change, all the optical signals of the unnecessary wavelength are not removed,
Part of it will be transmitted through the optical filter 44 and propagated.

Conventional connector ferrule with filter for optical fiber
Another embodiment of 50 is shown in FIG. This is to cut a certain portion of the connector ferrule element 51 at a certain selected predetermined angle θ with respect to a plane perpendicular to the axial direction of the optical fiber insertion hole 52, and set a curable resin between the cut end faces 53. The optical filter 54 is sandwiched via an adhesive 55 to be adhesively solidified. In order to bond and solidify the optical filter 54, first, an end surface 53 of a half body 57, which is a side of a ferrule half body having an end surface 53 cut at an angle θ, on which a plurality of wavelengths including unnecessary wavelengths are transmitted. Apply adhesive 55 to the optical filter 54
After sticking and adhering and solidifying, adhesive 55
Is applied and the cut end face 53 of the other cut ferrule half body 58 is stuck and adhered and solidified. In this case as well, the adhesive 55 is evenly applied on the cut end face 53 of the first ferrule half body 57. It is difficult to do so, even if it is applied evenly and the optical filter 54 is adhered in parallel to the surface,
The adhesive 55 is distorted by the heating for curing the adhesive 55,
It is difficult to bond and solidify the end surface 53 and the surface of the optical filter 54 in parallel. Reference numeral 56 in the drawing denotes a hole fiber inserted into the insertion hole 52.

Furthermore, as the curable resin adhesive, we selected and used one that is as close as possible to the refractive index of the optical fiber core, but even if there is a slight difference in the refractive index, the thickness of the adhesive coating layer As the thickness becomes thicker, the influence on the traveling direction of light becomes greater, so that even if the optical filter is mounted at a desired inclination angle accurately, the predetermined reflection does not occur.

[Means for Solving the Problems] The present invention relates to a method for attaching an optical filter to an end face having a predetermined angle with respect to an axis of a connector ferrule element for optical fiber via a curable resin adhesive. The adhesive is cured by heating the optical filter while pressing it toward the end face.

[Operation] According to the present invention, when the optical filter is attached to the end surface of the connector ferrule element via the adhesive,
Since the adhesive is hardened by heating the optical filter while pressing it toward the end face, the adhesive between the end face of the connector ferrule element and the optical filter protrudes from the gap, and the adhesive between them is extremely To be a thin film.
In addition, since the adhesive is heated and cured while being pressed, even if the adhesive distorts during curing, it is suppressed.

[Embodiment] An embodiment of manufacturing the connector ferrule half body 10 with a filter for optical fiber shown in FIG. 1 by the method of the present invention will be described with reference to FIG.

First, in FIG. 1, 11 is a connector ferrule half element, 12 is an optical fiber insertion hole provided in the axis thereof, and 13 is a selected predetermined angle θ with respect to a plane perpendicular to the axis. Connector Ferrule half element without
11 is an end face, 14 is an optical filter, 17 is a glass substrate thereof, 18 is an optical filter film formed on one side thereof, and the surface of the filter film 18 is directed to the end face 13 to bond the curable resin. It is adhesively hardened by the agent. 16 is the above insertion hole 12
It is an optical fiber that has been inserted into.

FIG. 2 is a manufacturing apparatus for explaining the method of manufacturing the connector ferrule half body 10 shown in FIG. 1 above, and 21 is an arm of the manufacturing apparatus 20, which is shown in FIG. The connector ferrule half element 11 is placed and fixed so that its end face 13 is horizontal. 22 is a movable arm connected to the above-mentioned arm 21 so as to be capable of rotating in a horizontal direction at a lower portion thereof;
Is a pressing rod which is attached to the movable arm 22 and which is constantly pushed upward, 24 is a compression spring attached to the pressing rod 23, and the end face of the pressing rod 23 is horizontal, and the connector feather is Rule half element 11
Of the optical filter between the end face 13 and the horizontal end face of the pressure rod 23.
It is sandwiched between 14. The glass substrate of the optical filter 14 is directed to the pressing rod 23 side.

In FIG. 2, first, with the optical filter 14 not yet placed on the end surface 13 of the connector ferrule half-element 11, an abrasive is placed on the tip of the pressing rod 23, and the half-element 11 is cut off. Move the arm while applying pressure to the end face 13 of
The end face 13 of the connector ferrule half-body element 11 is ground by vibrating 22 in the horizontal direction. Next, the end face 13 is coated with a curable resin adhesive, and the optical filter 14 is attached to the end face 13 with the surface of the filter film facing the end face 13 side, and the compression spring 24 of the pressing rod 23 is actuated, and the optical filter is applied. When a pressing force is applied to the end face 13 to the end face 13, the end face 13 and the optical filter are
The adhesive that exists between 14 and 14 is pressed thinly, and most of it is exposed to the outside. By doing so, even if the adhesive is unevenly applied, it is flattened by the pressure.

After this, connector ferrule half body element 11
While pressing force is applied to the optical filter 14 toward the end face 13 of the
By heating the portion to the curing temperature of the curable resin adhesive to cure the adhesive, the half of the connector ferrule with a filter for optical fiber is manufactured.

In the above, the case where the pressing direction is the direction perpendicular to the end surface 13 of the connector ferrule half body element 11 is shown, but the end surface of the pressing rod 23 is the same as the inclination angle of the end surface 13 of the half body element 11 in the opposite direction. As the inclination angle, a pressing force may be applied in the axial direction of the half element 11.
For heating for curing the adhesive, the apparatus shown in FIG. 2 may be placed in a heating chamber and heated, or a cartridge heater may be inserted in the axial center of the pressing rod 23 so that the optical filter is provided. At the same time as pressing 14 is applied, that portion may be heated.

FIG. 3 shows an assembly structure of a connector ferrule 30 with a filter for an optical fiber. 301 is a connector ferrule half body made by the manufacturing method of the present invention, an optical fiber insertion hole 32 is provided in the axial center of the half element 311 and an optical fiber 36 is inserted therein. The end surface 33 has a certain predetermined inclination angle θ,
An optical filter 34 having an optical filter film 38 formed on one surface of a glass substrate 37 is attached thereto by the method of the present invention. 302 is another connector ferrule half body combined with the above half body 301, and an optical fiber 36 is inserted through the through hole 32 of the axial center of the half element 312, and the end face 33 thereof is the half element. It has the same inclination angle as the inclination angle θ of the end face 33 of 311. These connector ferrule halves 301, 302 are butted in a sleeve 39, and a curable resin adhesive 35 is cured and bonded between them to complete an optical fiber filter thrust connector ferrule.

[Effect of the Invention] According to the method for manufacturing the connector ferrule of the present invention,
For attaching the optical filter to the end face of the ferrule half-body element having a predetermined inclination angle θ via the curable resin adhesive, the adhesive is cured while being heated while applying pressure thereto. Even if there is unevenness in the application of the adhesive to the end surface of the body element, the adhesive is pressed by the pressing force, and its thickness becomes thin and uniform. Therefore,
The filter film of the optical filter comes very close to the end face with the tilt angle θ and becomes parallel, and reflects the optical signal of a predetermined unnecessary wavelength as desired, so that it is transmitted to the opposite side of the connector ferrule. It can be lost. In addition, since the adhesive existing between the ferrule halves is made extremely thin by the above pressing, even if the refractive index between the adhesive and the optical fiber core may be slightly different, Has almost no effect on the traveling direction of the optical filter, and therefore has little effect on the tilt angle of the optical filter.

Further, even when the adhesive is cured, pressing force is applied between the optical filter and the end face of the connector ferrule during heating, so that distortion of the adhesive is suppressed, and as a result, the optical filter is It is possible to obtain the connector ferrule that is accurately attached to the end face at the angle θ.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of the structure of a connector ferrule half body with a filter for optical fiber, and FIG. 2 is for manufacturing the connector ferrule half body of FIG. 1 by the method of the present invention. FIG. 3 is a side view showing the embodiment of the manufacturing apparatus of FIG. 3, and FIG. 3 is a side sectional view showing the structure of a connector ferrule with a filter for optical fiber using the connector ferrule half body manufactured by the manufacturing method of the present invention. FIG. 4 (a) is a side sectional view showing an example of a conventional connector ferrule with a filter for optical fiber, FIG. 4 (b) is an enlarged sectional view of a cut portion of FIG. 4 (a), and FIG. FIG. 7 is a side sectional view showing an example of two conventional connector ferrules. 10, 301, 302, 57, 58; connector ferrule half, 30; connector ferrule manufactured according to the present invention, 40, 5
0; connector ferrule manufactured by a conventional method,
11, 311, 312; Connector Ferrule half element, 4
1, 51; connector ferrule element, 12, 32, 42, 5
2; optical fiber insertion hole, 13, 33, 53; end face, 43; notch,
14, 34, 44, 54; optical filter, 35, 45, 55; curable resin adhesive, 16, 36, 46, 56; optical fiber, 17, 37, 47; glass substrate, 18, 38, 48; optical Filter film, 39; sleeve, 20; connector ferrule half manufacturing device, 21; arm, 22; movable arm,
23; pressing rod, 24; compression spring.

Claims (1)

(57) [Claims] 1. An optical filter is placed on an end face of a connector ferrule having an end face at a predetermined angle with respect to an optical fiber communication hole of an axial center through a curable resin adhesive, and the end face is heated while being pressed. Then, a method of manufacturing a connector ferrule with a filter for an optical fiber, characterized in that an optical filter is attached to an end surface of the connector ferrule by curing the adhesive.